Fix alignment for Remove source branch checkbox

app/views/shared/issuable/form/_merge_params.html.haml

@@ -7,11 +7,10 @@
 -# This comment and the following line should only exist in CE.
 - return unless issuable.can_remove_source_branch?(current_user)
 
-.form-group
+.form-group.row
   .col-sm-10.offset-sm-2
     - if issuable.can_remove_source_branch?(current_user)
-      .form-check
-        = label_tag 'merge_request[force_remove_source_branch]' do
-          = hidden_field_tag 'merge_request[force_remove_source_branch]', '0', id: nil
-          = check_box_tag 'merge_request[force_remove_source_branch]', '1', issuable.force_remove_source_branch?
-          Remove source branch when merge request is accepted.
+      = label_tag 'merge_request[force_remove_source_branch]' do
+        = hidden_field_tag 'merge_request[force_remove_source_branch]', '0', id: nil
+        = check_box_tag 'merge_request[force_remove_source_branch]', '1', issuable.force_remove_source_branch?
+        Remove source branch when merge request is accepted.